The total cross section for top quark pair production close to threshold in e+e− annihilation is investigated. Details are given about the calculation at next-to-next-to-leading logarithmic order. The summation of logarithms leads to a convergent expansion for the normalization of the cross section, and small residual dependence on the subtraction parameter ν. A detailed analysis of the residua...

We examine the dependence of event rates at neutrino telescopes on the neutrino-nucleon cross section for neutrinos with energy above 1 PeV, and contrast the results with those for cosmic ray experiments. Scaling of the standard model cross sections leaves the rate of upward events essentially unchanged. Details, such as detector depth and cross section inelasticity, can influence rates. Numeri...

The zero to four loop contribution to the cross section Re+e− for e +e− −→ hadrons, when combined with the renormalization group equation, allows for summation of all leading-log (LL), next-to-leading-log (NLL) . . . N3LL perturbative contributions. It is shown how all logarithmic contributions to Re+e− can be summed and that Re+e− can be expressed in terms of the log independent contributions,...

We study the factorization scheme dependence of the next-to-leading order inclusive one jet cross section dσ/dET . The scheme is varied parametrically along the direction that transforms the MS scheme to the DIS scheme: we introduce a parameter λ such that λ = 0 is MS and λ = 1 is DIS. The factorization scale μ is also varied. We observe a change of ±9% in the cross section for ET = 50 GeV when...

General Diagnostic Tests for Cross Section Dependence in Panels This paper proposes simple tests of error cross section dependence which are applicable to a variety of panel data models, including stationary and unit root dynamic heterogeneous panels with short T and large N. The proposed tests are based on average of pair-wise correlation coefficients of the OLS residuals from the individual r...

The variation of the optical absorption of carbon nanotubes with their geometry has been a long-standing question at the heart of both metrological and applicative issues, in particular because optical spectroscopy is one of the primary tools for the assessment of the chiral species abundance of samples. Here, we tackle the chirality dependence of the optical absorption with an original method ...

We propose a nonlinear heterogeneous panel unit root test for testing the null hypothesis of unit-root processes against the alternative that allows a proportion of units to be generated by globally stationary ESTAR processes and a remaining non-zero proportion to be generated by unit root processes. The proposed test is simple to apply and accommodates cross section dependence. Monte Carlo sim...

The energy dependence of the capture cross section and the temperature dependence of the capture rate constants for inverse power attractive potentials V}2R is considered in the regime where the quantum character of the relative motion of colliding partners is important. For practically interesting cases n54 and n56, a simple formula for the cross section is suggested which interpolates between...

We perform calculations for the production of φ mesons in nuclei at energies just above threshold and study the A dependence of the cross section. We use results for the φ selfenergy in the medium obtained within a chiral unitary approach. We find a strong A dependence which is tied to the distortion of the incident proton and to the absorption of the φ in its way out of the nucleus. The effect...